Brake



Aug. 13, 1929. G, H. sToNER BRAKE Filed Aug. 26, 1925 .y ,mw m. l

.um/.m @m

15P /ff' Patented ug. 1 3, 1929.

UNITED STATES enoaen'n. sToNEn, or EnsT BOSTON, MASSACHUSETTS, ASSTGNOR, BY" MEsNE ASSIGN- MENTS, To sToNEa-AMES BRAKE COMPANY, TNO., Or- BOsTON, MASSACHUSETTS,

A CORPORATION F MAS'SACHSE'ITS.

BRAKE. j

Application filed August l26, 11926. Serial No. 131,613.

In my Vpresent invention I have provided certain improvements and'additions to my I former brake inventions as set forth .in Letters Patent No. 1,550,398, granted to me August 18, 1925.' Reference is made to that patent inasmuch as my present invention relates to a brake of similar type. V In the development of my previous' inventions'certain conditions were' met and difiicultie's encountered. Among these'was the requirement in certain instances for a greater clearance centrally of the brake, as for example, where a large hub or inner member was employed in connection with the wheel M or axle or where lateral displacements of any adjacent parts made such clearancenecessary. As illustrative otmy presentv invention I have shown in the accompanying drawings a term of brake involving the au novel features in forms well adapted to practical use and commercial production. These drawings are understood tobe illustrative of the embodiment rather than as limitingv in their nature and as such I shall proceed to describe the parts so illustratedas consti- -tuting my new brake. Throughout the specication and drawings like reference characters are correspondingly ap lied. 'Ihe characteristic Jform o my present in- 3a vention is shown in the accompanyingr drawings to whichreierence` is made in the appended specification through the' usual me dium of reference characters. In the drawings:

with brake shoes installed,

Fig. 2 is a plan view of the central arc bearing of the double strut chord members, and Fig. 3' is a fragment of an end block 40 sectioned to show the ball and socket-connection.

In the drawings I have indicated at 1 a usual lbrake drum within which I mount my novel brake Shoes. These preferably consist of the flexible arc members 3 which as explained in my prior Patent No. 1,550,398, are formed of somewhat resilient stock, be-` ing shaped to general curvature, but capable.. to produce variation in thel radius of curvature.

of being Hexe Ilhave indicated at`-12 a conventional cam member such as 1s usuallyemployed in ulezg- Fig. 1 is a side elevation of a brake'vdrum adapted to contact with the cam. .This block -panding brake shoes and at I I have indii 7 is riveted to the end of the are member 3 and at the opposite 'end of said arc member 3 is provided another rigid block 8 which is connected by an oppositely Ithreaded coupling 5 to one of a pair of hinge members 4 to provide for the circumferential adjustment ofthe shoes relative to-*the cam 12. The members 7 and 8 are each'tapped for connection with the chord members 9 as shown in the itorml selected V for illustration.

It will `be understood that there may be any number oit' these chord members, althoughy I have found that four usually gives sufficient clearance and adjustment forordinarytypes ot axle and hub design.

AThe connection between the chord members 9 and the blocks`7 and 8 maybe direct, as illustratlvely shown in connection with the block 7, or may -be indirect as by a ball and socket joint v91 as shown in Fig. At

their opposite ends the chord or strut members 9 are tapped into 4a pair of hinge meml bers 13 mounted 'on a pin 14.- in a pair of bracket ears 15. These bracket ears are located preferably midway between the castings 7l and 8 and operate'to give a resultant thrust u on the operation of the cam 12 centrally o the 'arc member B;

The action is something of a toggle joint action. and increases the certainty of uniform flexation of the band 3 especially in the case ofthe larger brake drums. While the oper* ation of the struts or chord members 9 throughtheir bearings is not exactly a toga gle action, this word is employed as suggestive of the flexation of'the slightly resilient arc4 member 3 by which it is warped or bent intermediate of its ends and Awith radial reference to its ends. That'is to say, the strut pair in the instance shown constitutes a cooperative subtending device which is capable of producingradial adjustment of the cnds relative' to the middle, or themiddle relative to the ends. These strut `rods y9 are held by l the lock nutsll. The usual brake lining is indicated by the reference character L and as in the Vcase of my previous inventions may be of any thickness or character gen- .erally used.

Various modifications 4may obviously be made in detail of structure. In those shown `I have followed merely the preferred form indicated in my previous, patents and applidesire to se- 1 ber comprising a flexible arc member, a pair of adjustable strut members each having a bearing at one end at the end of the are member, and'having a common bearingintermediate the ends ofl said are member for i adjustingi the curvature of that are.

2. In a brake, an internal ex ansion member comprising a pair of ieXi le arc members, a pair of adjustable struts for each member, and having a common bearing intermediate the ends of the are member for adjusting the curvature thereof.

3. In a brake, an internal expansion member comprising a flexible arc member, ad-

- justable struts having` bearings at points intermediate the operating diameter of the brake for adjusting the curvature of the arc member.

4. In a brake, an internal expansion shoe comprising a flexible arc member, and means for effecting a positive exation in independent regions of the arc. -n In testimony whereof I affix my signature.

' GEORGE H. STONER. 

